ERBB2 and neoplasm: Focussing on the 5 ASCO/CAP FISH groups, 62 patients (45.6%) showed a change in the FISH group pre- and post-treatment; 9.6% of HER2 amplified tumours (Groups 1, 2 and 3) changed FISH group whilst, 16.9% of HER2 non-amplified tumours (Groups 4 and 5) changed.